Automatic form generating machine



July 20, 1943. L M. TAYLOR AUTOMATIC FORM GENERATING MACHINE Filed Jan. 31. 1941 2 Sheets-Sheet 1 v //vvs--rOQ Les 752/1. 721 40 July 20,1943. L, TAYLOR 2,324,546

AUTOMATIC FORM GENERATING MACHINE Filed Jan..31, 1941 2 Sheets-Sheet 2 Patented July 20, 1943 1 AUTOMATIC FOIEIM GENERATING MACIiINE V e e Ilester Taylor, Ilaytornbhio Application January'31, 1941 Serial No. 376,859 sol-aims. (c ao-#131) i Granted under the. act of f3 as Q' amended April 30, 1328;370 0.

The invention described herein may be manufactured and used by or for the Government for governmental purposes, without the paymentto me of anyroyalty thereon. v

r This invention relates to mechanisms for, generating forms such as propeller blades and the like. e

.The invention more particularly relates to a mechanism for' accurately controlling, during machining, the variable dimensions which determine the propeller blade section.

In the design and construction of propeller blades, each section through the blade has a given width, thicknessyangle with respect to a given base, giving the blade desired aerodynamic characteristics, arid-another angle known as the blade-angle to compensate forlthe' displacement of thecenter of gravitydu'e to bending of-the propeller under load and centrifugal force} In the preferred embodiment of the invention, there is provided a master card for controlling the width and thickness of the blade at any given point on the blade and a system of cams opera-f tively associated with the master cam for modifying the effect; of the master cam at different pointsalong the length offthe blade. e The :c and component of a particular perim ete'r of the formto be generated is determined by a cam follower operatively engaging ajmaster' cam. The effective position of the cam;fol1ower is rnodified by a'system of cams as the master cam and cutting tool move longitudinally of the body. The system of cams modify notonly the :c and 3 components forwidth' and thickness but also shift the axis ofordinates to chang e theangle with respect to a given base and the blade-angle.

It isan object of this invention to reduce the shape of an object having four variables to a master cam modified by a separate camfor each variable, and to control-by means of th camsmechanism for generating a solid object.

Referring to the-drawings, Fig. 1 is a perspective view of a lathe incorporating the present invention.

Fig. 2 is an elevational view of the master cam,"

and" the auxiliarycams, the housing, with the cover plate removed, incorporating the 'mecha-] nism operated by the cams; In this view the driv ing mechanism shown inFig. 1 has been omitted.

for .the sake of clarity.

Fig. 31s a cross sectional iiewalong the lines 35 3 of Fig. "2:. f

Fig.4 is a cross-sectional viewfalong the lines;

Hg Fi .1 :2/1

portion of a G.- zav: y

Fig. 5 is across-sec 5+5 of Fig. 21" 3' Referringito thedrawing s, the work to be ma:

chined--a propeller in the preferred embodiment,

ofv *the inventionis rotatably. mounted on a. headstock 3 and spindle 4 oflathe 2 in position to be machined by 'tool5 carried by tool-carryingand-positioning member 6 slidablymounted on supporting and guiding member I.

able mechanism, a cutter 5. Attached to member. 6 by means of set screws or the like is a cover plate 48. Movement of member 6 lengthwise on.

the lathe is accomplished in a suitable manner by a connection for driving shaft 30; This driving connection includes a gear 3| integral with shaft v 30. and meshing with gear32v GearJ32 is integral with. onee'nd of shaft 33, while at the other end of'the shaft is a: gear'34.'-Shaft 36i has integral:

therewith l at. one; end a gear 35 meshing with gear 34 andatthe other. end a gear 31 meshing with gear-s8, :which .in turn is integral with splined shaft 8. Gearvl39 .is. mounted on splined therewith but to slide with? respect thereto.- Gears 3!! and 40 are-laterally positioned in relation to= member 6 by-meansofybracket 43 carried by.

member 6; ,Also carriedbysplined shaft 9-.to rotate therewith-but.to, slide with respect thereto as the result of aprojection (not shown) en-' tering gthe splineq 50.-is a Worm gear 4| meshing.

with a gear 42;;which in turn meshes with rack 45. Gear is positioned laterally in spaced relation to member 6 by means of bracket 44 car-" ried by member-B. It is .to be understood that the gears are so selectednas to :drive the member 6 at apreselected rate, also that a suitable clutch may be incorporated in the driving connection if desired. I l

.I'he longitudinal "position of cutter 5 is controlled by a master cam 61 and auxiliary cams or templates A, B, X, Y, (Fig. 2) which positionsthrough mechanismto be hereinafter more fully described-a pin 58. The position of pin 58 de-= termines the contour of the blade at any particular location lengthwiseof the blade. l The center of gravity of the section to be generated corresponds to the center of, rotation of the cam and cam follower. -Thus in Fig.- 2, the

center of gravity for aparticular section of the blade is shown as -c. g. and the coordinates onal 'yiew along the lines Carried by. member 6 isa motor 16 for driving through suit- 2311 1 of a point on the section as located by the center of pin 58 is $1111. The coordinates of the cam follower 65-considering the center of pin 69 as the axis of ordinates-is :coyo. Since the value of $1 corresponds to the value of am as modified by the a: cam thru pin |||-which determines the angle A. of lever |09--it follows that ar1=a:o tan Ax. Similarly 1111:1110 tan Ay..

Pin 58 moves in response to movement of cam follower 85 having a roller 66 (Fig. 3) for en.- gaging the face and following the trace of master cam 6?. Cam follower 65 is carried with freedom for sliding movement by cam follower carrying arm 68, which in turn has a cut-out portion 89a (Fig. 3) for receiving the cam follower and also for receiving a spring 10 adapted to maintain the cam follower in engagement with the trace of cam 61. Follower 65 is provided with suitabl guiding projections (Fig. 5.) for preventing relative lateral movement between carrier arm 68 and follower 65. Arm 68 is pivotally mounted on shaft 69 carried by brackets 13 and I4 (Fig. 5) which are in turn suitably fastened to cam carrier 15. Cam member 6'! is mounted for limited rotative movement about the center of shaft 69 constituting an axis of ordinates as designated by X-X and Y--Y axes drawn therethrough. Cam carrier member is provided with a pair of lugs I6 and TI into which is threaded pins I8 and I9 receivable in slots 80 and 8| of cam member 61 for limiting the rotation of that member. Rotation of cam member 61' is effected by arm 82 suitably, rigidly fastened thereto. Arm 82 and cam member 61 are urged to rotate in clockwise direction by spring 83. The position of arm 82 is controlled by pin 86, slidably received in opening 84, and engaging pitch controlling cam B which controls the position of pin 86 and the degree of rotation of the cam member 61. Arm 82 and pin 86 are in sliding bearing engagement. at 85.

Cam member 61 and cam carrier 15 are slidably supported on back plate 38 to move in response to blade-angle controlling cam A. Pin 87, integral with cam carrier I5, operatively engages blade-angle controlling cam A. Guide members 88 and 89, Fig. 2' are provided for cam carrier I5.

Cam member 61 is thus shown to be slidable and rotatable in response to changes in two variables in the shape of the form generated.

The width and thickness of the blade section, consistent with changes in blade pitch and blade angle, is controlled by the position of cam follower 85. The horizontal position of the cam follower hereinafter known as the abscissa, governs the horizontal position of pin 58 by means of bracket 98, which in turn is guided for vertical sliding movement on frame 9| by guiding means 92. Bracket. 90 is provided with an arm 93 slotted to receive portion 94 of cam follower 65.: Vertical movement of cam follower 65' is transmitted by arm 93 to bracket 90 which in turntransmits the motion by slotted arm 94 to pin 95. Pin 95 slides along arm 96 in response to movement of arm 94. resulting in horizontal movement of arm 9 of bracket 98 which in turn is transmitted to arm 63 and pin 58 Arm 96 is provided with aguide portion 99' for receiving pin 95. The position of arm 96 for any position lengthwise of the blade is governed by cam Y. Pin; I80, vertically, slidably mounted in frame 9|, slidably engages cam Y and also engages arm 96' at I III with freedom for relative sliding movement. Spring I02 urges arm 96' to engagement with pin I00 and is sufficiently stiff to hold arm 96 against movement when pin 95 is being moved by arm 94.

Horizontal movement of cam follower 65 is transmitted to slotted arm I04 of bracket I05 which is horizontally, slidably mounted on frame 9|. Bracket I has integral therewith a slotted arm N36 for receiving pin, |0,'|. Washers I24 and cotter pins I25 serve to position pin I01 laterally (Fig. 4). Pin I0! is slidably received in guide-way III] of arm I09, pivotally connected at Ill to frame 9|. The position of arm I09 for any""position lengthwise of the blade is governed by cam X. Pin II I, mounted for'vertical sliding movement in frame 9|, slidably engages cam X 3 at one end and engages arm I09 at 2 for pivotal sliding movement with respect thereto. Spring II3, attached at one end to arm I09 and at the other end to frame 9|, holds arm I09 in operative engagement with cam X. Movement of bracket I05 transmits the horizontal component of the motion to pin I01 which'in turn rides: on arm I09 in guide-way H0, moving arm I08, bracket H5 and arm ||6 vertically tov move pin 58 a corresponding amount. Spring ||3 has sunicient initial tension to prevent upward movement of pin I01 and arm I09 under action of bracket I85.

The position of pin 58 determinesthrcugh suitable servo-mechanism (not shown)-the"position of the cutter 5. Since the position of pin 58 is determined by the master cam as modified by the auxiliary cams, it is only necessary to change the master cam or one of the auxiliary cams, ,or any combination of them in order to change the blade characteristics.

Various changes may'be made in the device without departing from the spirit of the invention, it being intended to be limited only by the terms of the appended claims.

I claim:

1. A device adapted to be associated with a tool and servo mechanism for operatively positioning the same to shape an object, which object in its completed form varies in width, thick.- ness, angle of pitch which one dimension of the object makes with respect toa given plane, and angle which the length of the blade makes with respect to a given plane; comprising rotatably and slidably mounted master cam, means for controlling'the rotation of said cam. in accordance with changes in the said angle of pitch, means for controlling the sliding of the said cam in accordance with changes in the said angle whichthe length of the .blade makes with re-. spect to a given plane, a cam follower for engaging said cam for determining the width and thickness of the said object, and formodifying the effect of the said cam follower.

2. A device adapted to be associated with a tool and mechanism for operatively positioning the same to shape an object which in its completed form varies in Width, thickness, angle of pitch which one dimension of the blade makes with respect to a given plane, and angle which the length of the blade makes. with respect to a given plane; comprising a rotatably and slid-v ably mounted master cam, means including a template for rotating the cam to correspond to the said angle of pitch, means including a. template for sliding said cam to correspond to the said angle which the length of the blade makes with respect to a given plane, a cam follower for engaging said cam to determine the width and thickness of the said object, and templates; for modifying the width and thickness deter of the object makes with respect to a given plane and angle which the length of the blademakes with respect to a given plane; comprising a rotatably and slidably mounted master cam, the

trace of the said master cam having incorpoa rated therein the said width and thickness dimensions, means for controlling the rotation of said cam in accordance with changes in the said angle "of pitch, means for controlling the sliding of said cam in accordance with changes in the said angle which the length of the blade makes with respect to a given plane, a cam i01- lower, and means connecting said cam follower 10 to said positioning mechanism.

LESTER M. TAYLOR. 

